Scientists develop tool that analyses the change of bacteria in gut of astronauts

The tool by researchers at North­west­ern Uni­ver­si­ty is called STARMAPS. It was used to analyse the data from dif­fer­ent exper­i­ments, includ­ing mice sam­ples, NASA’s Twin Study and Earth-based stud­ies on the effects of radi­a­tion on the gut. (Rep­re­sen­ta­tive pho­to: Get­ty Images/Thinkstock)

Researchers at North­west­ern Uni­ver­si­ty in the US have recent­ly devel­oped a new tool that shows that space­flight, both when astro­nauts are aboard a space shut­tle or when they are in the Inter­na­tion­al Space Sta­tion (ISS), con­sis­tent­ly affects the microor­gan­isms in their gut.

The tool is called STARMAPS (Sim­i­lar­i­ty Test for Accor­dant and Repro­ducible Micro­bio­me Abun­dance Pat­terns) and it got used to analyse the data from dif­fer­ent exper­i­ments, includ­ing mice sam­ples (rang­ing from Rodent Research‑1 to 7), the US space agency’s Twin Study and Earth-based stud­ies on the effects of radi­a­tion on the gut.

As per a wide range of data, mice on the space shut­tle and on ISS went through changes sim­i­lar to that of NASA astro­naut Scott Kel­ly dur­ing his 11 months stay in space. The new study also sug­gests that such changes in micro­bio­mes are most like­ly to have been caused because of the micro­grav­i­ty, instead of radi­a­tion, as per a state­ment by North­west­ern Uni­ver­si­ty. The research study was pub­lished last month in the jour­nal Micro­bio­me.

“Radi­a­tion def­i­nite­ly has an effect on the gut micro­bio­me,” Martha Vita­ter­na, the lead author of this study said in the state­ment. “But those effects do not look like what we saw in space­flight,” she added.

The research looked at mouse sam­ples from the final NASA space shut­tle mis­sion, STS 135, which launched in 2011 and also the sam­ples from sev­en mice groups which were sent to ISS as a part of Rodent Research mis­sion by NASA.

The changes that the researchers observed in the mice groups on ISS were com­pared to that of a ground con­trol group, a base­line group and a lab­o­ra­to­ry group that was housed in a con­ven­tion­al mouse facil­i­ty. In addi­tion to this, data from NASA’s Twin Study which com­pared phys­i­o­log­i­cal changes in NASA astro­naut Scott Kel­ly to his Earth-bound twin, Mark.

Though the research showed that space­flight does cause changes in the bac­te­r­i­al diver­si­ty in the gut micro­bio­me, the exact cause of the change was not very clear.

“There wasn’t a sta­tis­ti­cal approach for doing this work,” Vita­ter­na said in her state­ment. “The tools didn’t exist, so we invent­ed them. It’s a clas­sic case of how neces­si­ty is the moth­er of inven­tion.”

With the help of STARMAPS, the researchers could iden­ti­fy the pat­terns where dif­fer­ent types of bac­te­ria become more or less abun­dant under dif­fer­ent con­di­tions. The study showed sim­i­lar types of changes in the space­flight and ground con­trol mice when com­pared with the oth­er two mice groups.

The data fetched from NASA’s Twin Study also showed a sim­i­lar pat­tern of micro­bio­me changes in NASA astro­naut Scott Kel­ly. The find­ings from the research sug­gest that gut micro­bio­me changes can be com­pared among mul­ti­ple space­flights, accord­ing to the researchers.

“If we are going to send humans to Mars or on long mis­sions to the moon, it is essen­tial to under­stand the effects of long-term expo­sure of the space envi­ron­ment on us – and on the tril­lions of bac­te­ria trav­el­ing with us,” Fred W. Turek, the co-author of the study said in the state­ment.

There were some dif­fer­ences in the micro­bio­me changes that were observed between the mice groups on space­flight and ground con­trol groups, which showed that the habi­tat holds the key.

Ear­li­er research­es on the radi­a­tion effects on mice micro­bio­me did not show the same pat­tern of micro­bio­me changes so the researchers feel that micro­grav­i­ty might have an effect on the gut micro­bio­me, how­ev­er fur­ther research is need­ed to be done.

“Under­stand­ing what genet­ic fac­tors con­tribute to dif­fer­ences in bac­te­r­i­al strains will be use­ful for devel­op­ing coun­ter­mea­sures that can pro­tect your micro­bio­me dur­ing stress­ful peri­ods,” Vita­ter­na said in the state­ment.